The boy let out a breath that had been filling him up to near-bursting.  Jay had put the fire out before it had eaten away at the rest of the shop and all of Knockturn Alley.  He couldn't even imagine what Simeon and the aurors would have done to him if that had occurred.  Had the fire been a punishment for him having stolen it from the shop?  But he hadn't been the one to snatch it in the first place, nor had he been cursed with fire for nicking other items. 

"Thanks," he whispered out in relief. 

Once it seemed fully extinguished, Eli started rooting about the wet mess for the culprit.  The toe of his boot found the handle of the knife.  The blade was still exposed as he'd dropped it in his panic.  Instead of picking it up, he took a giant step backward and pointed meaningfully at it.  The expression he shot Jay was one of anxiety.  Would the fire re-start if he touched it again?  He didn't want to take that chance.